Both the monograph by R. J. Gornall and B. A. Bohm (1985) and the molecular systematic work of D. E. Soltis et al. (1993) support a close relationship among Bolandra, Boykinia, and Suksdorfia. Other genera that appear to be closely related to these are Jepsonia, Sullivantia, and Telesonix (Soltis et al.).